WordPress trackback problem FINALLY SOLVED….
For around 3-4 months now I’ve had a REALLY annoying problem with the wordpress install on this site. Trackbacks suddenly stopped working. Somewhere around my 800th post or so while the WMF vulnerability was circulating (between Christmas and New Years) and I was typing furiously – poof…. suddenly trackbacks stopped going out. (Incoming trackbacks seemed to work just fine…) What’s had me stumped for so long is that I host 2 (now three) other sites off the same domain and I haven’t had a problem with ANY of those sending pingbacks or trackbacks.
At one point I thought maybe a trackback in the “queue” was stuck and used one of the suggested fixes to zero out the mysql field that holds information on sites to_ping (in wp_post…) In fact, there is a specific phpmyadmin sql query I’ve tried several times…. Update wp_posts set to_ping=”
Which hasn’t made things work.
Of course, I just upgraded to WordPress 2.0.2 and I had hoped that somehow magically the upgrade would make things start working again. The upgrade did no such miracle, so… quite weary of doing manual trackbacks I decided I’d research this evening. Additionally, I had the new odd behaviour of a blank page showing up when I edit or add a post… the address bar would read http://mysite.com/wp-admin/post.php but the page would be blank. Refreshing would bring up the post page, but it was inconvenient and annoying.
So… to summarize….. I’ve got 4 wordpress installs on one site (in one VPS), one suddenly stopped trackbacking the others worked fine. The only difference I can think of is the site that stopped trackbacking has over 1000 posts, the next closest is maybe 300 posts. Along the way of my research, I discovered that you can go to http://yoursite.com/wp-admin/execute-pings.php which seems like a good workaround (although automatic pings that wordpress “figures out” with another wordpress install don’t seem to go this way….)
What really made the breakthrough for me though was the discussion thread for this post… A comment from Antiorario who was suffering from the same wordpress problem…. mentioned that in his .htaccess file he added….. “php_value memory_limit 16M” which didn’t make trackbacks automatically when publishing a post, but DID enable the execute-pings.php to work….
Now, this moment was the classic – AHA…. I looked in the vps at /etc/php.ini (which is where php is configured…) and found….. memory_limit = 8M
I changed it to 32MB (I guess I could have tried 16 first… but …. in the other persons example 16M wasn’t quite enough to solve the ENTIRE problem.)…. I restarted the VPS and voila voici…. pingbacks/trackbacks now work…. In fact, I now don’t get the blank page after publishing or modifying a post….
So, in sum….
If you have a problem with outgoing trackbacks, or any other problem where it appears that wordpress has done some work, but has unexpectedly quit at some point, check and see (if possible) what the php memory limit is…. If you have access to your php.ini you can change the limit there, as I did, or you can try including something like “php_value memory_limit 32M” (without the quotes) in your .htaccess if you can’t access php.ini. Frankly I wasn’t sure you could override the php memory limit from .htaccess…
After 4 months of tolerating that problem….